A party of surveyors are sent into the wilds of Africa to survey the country for a proposed railway. They experience much difficulty as the natives are unfriendly and the country is infested with savage beasts. They establish a night watch in the ruins of an old house in order that they may guard their work from the malicious attempts upon the part of the natives to destroy it, but each night the watchman disappears mysteriously. Only traces of his blood are to be found. This goes on for two nights, and two watchmen disappear in a mysterious manner. At last the chief sends his last man to fetch help and goes himself to keep the night watch. The lions have done the work which the natives feared to do, and two of the white men have already been devoured by these savage brutes. The natives dig a deep pit right across the road along which all help must come to the Chief, left all alone with the wife of one of his men. They cover the pit with twigs and leaves so cleverly that the lion, whilst making the usual evening visit to the deserted house, falls into it. Thus the natives kill their ally, and save the white men for whom they really prepared the pit. Help arrives in due course, and the natives are subjugated, while the man eater meets his death within the pit.